WASHINGTON (AP)  Republicans roundly scolded their own presidential candidate Monday, demanding Donald Trump apologize for  and just stop  talking about the ethnic background and impartiality of the American judge overseeing a lawsuit against Trump University.

Leading the roll call were two former rivals for the Republican presidential nomination.

Ohio Gov. John Kasich tweeted that Trump”s offensive against the impartiality of U.S. District Judge Gonzalo Curiel “is flat-out wrong.”

Other prominent Republicans piled on, drawing a solid line between themselves and the billionaire candidate with whom they”ve developed a fragile peace. But that detente comes with caveats  chief of which is the understanding that Trump, nomination nearly in hand, will now focus on uniting the fractured GOP.

Trump, too, showed some deference for the truce, declining to immediately hit back at the Republican lawmakers who have demanded he move on.

But no mea culpa seemed forthcoming from the billionaire candidate. Trump insisted earlier Monday that his criticism of Curiel came in defense against relentless questions from reporters and others about lawsuits against Trump University. Trump said Curiel can”t be impartial in the suits because the jurist”s parents were born in Mexico and Trump wants to build a wall along the border. Last week, he denied on CNN that his remarks are racist.

“Public Service Announcement: Saying someone can”t do a specific job because of his or her race is the literal definition of ”racism,”” tweeted Sen. Ben Sasse, R-Neb., a longtime Trump critic.

Curiel is a former federal prosecutor who was born in Indiana to parents who came from Mexico in the 1920s. He has not responded to Trump”s attack, and Trump”s legal team has not sought his removal from the case. Judges generally are thought to have conflicts of interest only in more specific situations, such as a financial interest in the outcome of the case.

Trump University is the target of two lawsuits  in San Diego and New York  which accuse the business of fleecing students with unfulfilled promises to teach them secrets of success in real estate. Trump has maintained that customers were overwhelmingly satisfied. Curiel is presiding over the suits in California.

“All I”m trying to do is figure out why I”m being treated so unfairly by a judge,” Trump said Monday on Fox News Channel.

The Republican establishment responded in rare unison: Just stop.

“He needs to stop saying it. That man is an American  born in the United States,” Rubio, son of Cuban immigrants, told Orlando television station WFTV. “I don”t think it reflects well on the Republican Party. I don”t think it reflects well on us as a nation.”

Added Republican Sen. Susan Collins of Maine: “Donald Trump”s comments on the ethnic heritage and religion of judges are absolutely unacceptable. His statement that Judge Curiel could not rule fairly because of his Mexican heritage does not represent our American values.”

And from the House side, Oversight and Government Reform Comimttee Chairman Jason Chaffetz urged Trump to “move on.”

“Why doesn”t he just say, ”Look, it”s up to the attorneys” … and leave it at that?” Chaffetz, R-Utah, said on Fox News Channel.

The cascade of condemnation began on the Sunday talk shows, when a trio of prominent Republicans firmly rejected Trump”s focus on Curiel and urged him to make good on his promise to unite the fractured Republican Party. Senate Majority Leader Mitch McConnell said he “couldn”t disagree more” with Trump”s statements about Curiel”s impartiality, adding that “we”re all behind him now”  an implicit warning that such unity might not be the case for long. Senate Foreign Relations Committee Chairman Bob Corker said he doesn”t condone Trump”s statements about Curiel, then complained that his interview was supposed to be about foreign policy.

And former House speaker Newt Gingrich pointedly suggested that Trump start acting like “a potential leader of the United States.”

Trump already has rejected calls for him to adjust his approach.

“I”m not changing,” he said Tuesday at a fiery news conference at Trump Tower.

On Sunday, Trump doubled down on the idea. Asked on CBS whether a Muslim judge would be unfair given Trump”s plan to ban Muslims from entering the U.S., Trump responded: “Yeah. That would be possible, absolutely.”

That puts Trump in significant conflict with the Republicans he hopes to lead  including many of the ones who have opted to support him.